Field of the Invention
The invention relates to a motor controller and a brushless DC motor comprising the same.
Description of the Related Art
A typical controller for a brushless DC motor includes a control box, a circuit board, a dissipater, and an IGBT (Insulated Gate Bipolar Transistor) module. The circuit board is arranged inside the control box, and the dissipater is arranged on an inner wall of the control box. The IGBT module is disposed on the dissipater and is in electric connection with the circuit board, and the dissipater and the control box directly contact with each other. Such a structure has a potential danger of electrical leakage and a poor insulating effect.
The brushless DC motor includes a housing, a stator assembly, a rotor assembly, a front-end cover, a rear-end cover, a control box, and a circuit board. The stator assembly surrounds the rotor assembly, and the housing and the stator assembly are connected together. The front-end cover and the rear-end cover are disposed on two ends of the housing. The circuit board is disposed inside the control box, the control box is provided with a plurality of mounting holes, and the rear-end cover is provided with a plurality of threaded holes. A screw bar passes through the mounting hole and is inserted into the corresponding threaded hole for fixing the control box on the rear-end cover. A contact position between the mounting hole and the screw bar is sealed by a seal washer. However, when the motor is applied to an outdoor unit of an air-conditioner, the seal washer easily ages, and water easily penetrates into the motor and is difficult to be drained out, which results in short circuit of the motor and poor waterproof and drainage performance